x86/fpu: Rename XSAVE macros

There are two concepts that have some confusing naming:
 1. Extended State Component numbers (currently called
    XFEATURE_BIT_*)
 2. Extended State Component masks (currently called XSTATE_*)

The numbers are (currently) from 0-9.  State component 3 is the
bounds registers for MPX, for instance.

But when we want to enable "state component 3", we go set a bit
in XCR0.  The bit we set is 1<<3.  We can check to see if a
state component feature is enabled by looking at its bit.

The current 'xfeature_bit's are at best xfeature bit _numbers_.
Calling them bits is at best inconsistent with ending the enum
list with 'XFEATURES_NR_MAX'.

This patch renames the enum to be 'xfeature'.  These also
happen to be what the Intel documentation calls a "state
component".

We also want to differentiate these from the "XSTATE_*" macros.
The "XSTATE_*" macros are a mask, and we rename them to match.

These macros are reasonably widely used so this patch is a
wee bit big, but this really is just a rename.

The only non-mechanical part of this is the

	s/XSTATE_EXTEND_MASK/XFEATURE_MASK_EXTEND/

We need a better name for it, but that's another patch.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: dave@sr71.net
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20150902233126.38653250@viggo.jf.intel.com
[ Ported to v4.3-rc1. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

3 files changed, 19 insertions, 18 deletions

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 2fbea2544f24..156441bcaac8 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -30,7 +30,7 @@ static u32 xstate_required_size(u64 xstate_bv, bool compacted)
 	int feature_bit = 0;
 	u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
 
-	xstate_bv &= XSTATE_EXTEND_MASK;
+	xstate_bv &= XFEATURE_MASK_EXTEND;
 	while (xstate_bv) {
 		if (xstate_bv & 0x1) {
 		        u32 eax, ebx, ecx, edx, offset;
@@ -51,7 +51,7 @@ u64 kvm_supported_xcr0(void)
 	u64 xcr0 = KVM_SUPPORTED_XCR0 & host_xcr0;
 
 	if (!kvm_x86_ops->mpx_supported())
-		xcr0 &= ~(XSTATE_BNDREGS | XSTATE_BNDCSR);
+		xcr0 &= ~(XFEATURE_MASK_BNDREGS | XFEATURE_MASK_BNDCSR);
 
 	return xcr0;
 }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a60bdbccff51..2d4e54db49af 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -662,9 +662,9 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
 	/* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now  */
 	if (index != XCR_XFEATURE_ENABLED_MASK)
 		return 1;
-	if (!(xcr0 & XSTATE_FP))
+	if (!(xcr0 & XFEATURE_MASK_FP))
 		return 1;
-	if ((xcr0 & XSTATE_YMM) && !(xcr0 & XSTATE_SSE))
+	if ((xcr0 & XFEATURE_MASK_YMM) && !(xcr0 & XFEATURE_MASK_SSE))
 		return 1;
 
 	/*
@@ -672,23 +672,24 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
 	 * saving.  However, xcr0 bit 0 is always set, even if the
 	 * emulated CPU does not support XSAVE (see fx_init).
 	 */
-	valid_bits = vcpu->arch.guest_supported_xcr0 | XSTATE_FP;
+	valid_bits = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FP;
 	if (xcr0 & ~valid_bits)
 		return 1;
 
-	if ((!(xcr0 & XSTATE_BNDREGS)) != (!(xcr0 & XSTATE_BNDCSR)))
+	if ((!(xcr0 & XFEATURE_MASK_BNDREGS)) !=
+	    (!(xcr0 & XFEATURE_MASK_BNDCSR)))
 		return 1;
 
-	if (xcr0 & XSTATE_AVX512) {
-		if (!(xcr0 & XSTATE_YMM))
+	if (xcr0 & XFEATURE_MASK_AVX512) {
+		if (!(xcr0 & XFEATURE_MASK_YMM))
 			return 1;
-		if ((xcr0 & XSTATE_AVX512) != XSTATE_AVX512)
+		if ((xcr0 & XFEATURE_MASK_AVX512) != XFEATURE_MASK_AVX512)
 			return 1;
 	}
 	kvm_put_guest_xcr0(vcpu);
 	vcpu->arch.xcr0 = xcr0;
 
-	if ((xcr0 ^ old_xcr0) & XSTATE_EXTEND_MASK)
+	if ((xcr0 ^ old_xcr0) & XFEATURE_MASK_EXTEND)
 		kvm_update_cpuid(vcpu);
 	return 0;
 }
@@ -2906,7 +2907,7 @@ static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu)
 	 * Copy each region from the possibly compacted offset to the
 	 * non-compacted offset.
 	 */
-	valid = xstate_bv & ~XSTATE_FPSSE;
+	valid = xstate_bv & ~XFEATURE_MASK_FPSSE;
 	while (valid) {
 		u64 feature = valid & -valid;
 		int index = fls64(feature) - 1;
@@ -2944,7 +2945,7 @@ static void load_xsave(struct kvm_vcpu *vcpu, u8 *src)
 	 * Copy each region from the non-compacted offset to the
 	 * possibly compacted offset.
 	 */
-	valid = xstate_bv & ~XSTATE_FPSSE;
+	valid = xstate_bv & ~XFEATURE_MASK_FPSSE;
 	while (valid) {
 		u64 feature = valid & -valid;
 		int index = fls64(feature) - 1;
@@ -2972,7 +2973,7 @@ static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu,
 			&vcpu->arch.guest_fpu.state.fxsave,
 			sizeof(struct fxregs_state));
 		*(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)] =
-			XSTATE_FPSSE;
+			XFEATURE_MASK_FPSSE;
 	}
 }
 
@@ -2992,7 +2993,7 @@ static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu,
 			return -EINVAL;
 		load_xsave(vcpu, (u8 *)guest_xsave->region);
 	} else {
-		if (xstate_bv & ~XSTATE_FPSSE)
+		if (xstate_bv & ~XFEATURE_MASK_FPSSE)
 			return -EINVAL;
 		memcpy(&vcpu->arch.guest_fpu.state.fxsave,
 			guest_xsave->region, sizeof(struct fxregs_state));
@@ -7001,7 +7002,7 @@ static void fx_init(struct kvm_vcpu *vcpu)
 	/*
 	 * Ensure guest xcr0 is valid for loading
 	 */
-	vcpu->arch.xcr0 = XSTATE_FP;
+	vcpu->arch.xcr0 = XFEATURE_MASK_FP;
 
 	vcpu->arch.cr0 |= X86_CR0_ET;
 }
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 2f822cd886c2..f2afa5fe48a6 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -180,9 +180,9 @@ int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
 bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn,
 					  int page_num);
 
-#define KVM_SUPPORTED_XCR0     (XSTATE_FP | XSTATE_SSE | XSTATE_YMM \
-				| XSTATE_BNDREGS | XSTATE_BNDCSR \
-				| XSTATE_AVX512)
+#define KVM_SUPPORTED_XCR0     (XFEATURE_MASK_FP | XFEATURE_MASK_SSE \
+				| XFEATURE_MASK_YMM | XFEATURE_MASK_BNDREGS \
+				| XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512)
 extern u64 host_xcr0;
 
 extern u64 kvm_supported_xcr0(void);